So after putting the 454 in my 84 Z28 I removed the tank and cleaned it and had a shop weld on a sump and now the question is what to do with the stock 4 lines on the sending unit? How does the vent line get altered to still be used and what is a good method of capping the lines if needed? Are there any aftermarket sending units avaliable with just the vent for a stock tank? I've tried search and didn't find the answer I needed. Also all the stock fuel lines have been completly removed underneath the car. Just looking for help to get the tank back in as soon as possible.

 

Just leave the vent and evap lines as they are. Do you have the return on the sump or not? If not, leave the return as is also. The feed is the easiest to seal up. All you need is to find an o ring seat plug that will fit the line. If you don't care about ever using it again, cut it off and braze it shut.